(BBC) – Four people have died in an explosion at a shop in Leicester.
Residents said they heard “a big thud, like an earthquake” at the time of the blast in Hinckley Road at about 19:00 GMT on Sunday.
Four other people remain in hospital, one with serious injuries, Leicestershire Police said.
Supt Shane O’Neill said police believe there may be more people unaccounted for and rescue efforts were continuing on Monday.
At this stage the explosion is not being linked to terrorism, he added.
The building consisted of a shop premises on the ground level and a two-storey flat above.
Witnesses said the shop was formerly a Londis but recently became a Polish supermarket.
Matt Cane, group manager at Leicestershire Fire and Rescue Service, said the bodies of the four people were found during the search of the building.
He added fire crew were still working to find survivors who may be trapped in “voids” inside the collapsed building.
“When you look at the pictures of the building it looks incredibly unlikely that we would find anybody but we are absolutely committed to search and rescue at this stage,” he said.
“There is a possibility that there could be voids and areas of the building where people could still be alive following the collapse.”
Gas network Cadent said it had assisted emergency services on Sunday night by “isolating the gas supply” to the building and adjoining properties on Hinckley Road.
Supt O’Neill, from Leicestershire Police, said he “can’t say at this stage” what may have caused the explosion.
“It is a joint investigation between the fire service and the police and the priority is to make the area safe,” he added.
He urged anyone who knows someone who is missing to contact police, adding: “It is still a search and rescue operation. It is important we try and find as many people as possible.”